//
// Created by ub on 2020/11/1.
//
#include <iostream>
#include <cmath>
using namespace std;
struct polar{
   double distance; // distance from origin
   double angle; // 角度
};
struct rect {
   double x;
   double y;
};
polar rect_to_polar(rect xypos);
void show_polar(polar dapos);
/*int main ()
{
    rect rplace;
    polar pplace;
    cout << "Enter the x and y values: ";
    while(cin >> rplace.x >> rplace.y)
    {
       pplace = rect_to_polar(rplace);
       show_polar(pplace);
       cout << "Next two numbers (q to quit): ";
    }
    cout << "Done.\n";
    return 0;
}*/
// 值传递
polar rect_to_polar(rect xypos)
{
    polar answer;
    answer.distance = sqrt(
            xypos.x * xypos.x
              +
            xypos.y * xypos.y
            );
    answer.angle = atan2(xypos.x , xypos.y);
    return answer;
}
void show_polar (polar dapos)
{
    const double Rad_to_deg = 57.29577951;
    cout << "distance= " << dapos.distance;
    cout << ", angle = " << dapos.angle * Rad_to_deg;
    cout << " degrees\n";
}
